.\" -*- nroff -*-
.\" Copyright © 2015-2023 Inria.  All rights reserved.
.\" See COPYING in top-level directory.
.TH HWLOC-GATHER-CPUID "1" "%HWLOC_DATE%" "%PACKAGE_VERSION%" "%PACKAGE_NAME%"
.SH NAME
hwloc-gather-cpuid \- Dumps the relevant x86 cpuid values
for later (possibly offline) usage
.
.\" **************************
.\"    Synopsis Section
.\" **************************
.SH SYNOPSIS
.
.B hwloc-gather-cpuid [\fIoptions\fR] [\fI<outdir>\fR]
.
.\" **************************
.\"    Options Section
.\" **************************
.SH OPTIONS
.
.TP
\fB\-c <idx>
Only gather cpuid values for logical processor whose OS/physical index
is <idx>.
.TP
\fB\-q\fR \fB\-\-quiet\fR \fB\-s\fR \fB\-\-silent\fR
Do not show verbose messages.
.TP
\fB\-\-version\fR
Report version and exit.
.TP
\fB\-h\fR \fB\-\-help\fR
Display help message and exit.
.
.\" **************************
.\"    Description Section
.\" **************************
.SH DESCRIPTION
.
\fBhwloc-gather-cpuid\fR dumps all the relevant x86 cpuid values into
subdirectory \fIcpuid\fR of current directory,
or in \fB<outdir>\fR if specified.
.
.PP
These files can be used later to explore the machine topology offline,
for instance by setting the environment variable \fIHWLOC_CPUID_PATH\fR
to the directory containing all output files,
and by forcing the x86 backend with \fIHWLOC_COMPONENTS=x86,stop\fR.
.
.PP
The directory contents may also be submitted to hwloc developers
to debug issues remotely.
.
.PP
If \fB-\fR is used as <outdir>, the output is dumped to the standard
output, but a unique logical processor must have been given with \fB-c\fR.
.
.PP
\fBhwloc-gather-cpuid\fR is a x86 specific tool, it cannot be used
on other platforms.
.
.PP
.B NOTE:
\fBhwloc-gather-cpuid\fR gathers many hardware details about the platform.
Output files should not be posted on public lists or websites
unless it is clear that they contain no sensitive information.
.
.PP
.B NOTE:
The output of \fBhwloc-gather-cpuid\fR is included in the tarball
saved by \fBhwloc-gather-topology\fR on Linux/x86.
.
.PP
.B NOTE:
It is highly recommended that you read the hwloc(7) overview page
before reading this man page.
.
.\" **************************
.\"    Examples Section
.\" **************************
.SH EXAMPLES
.PP
To store cpuid information of all logical processors of the current machine:

        $ hwloc-gather-cpuid
        Gathering in directory ./cpuid ...
        Gathering CPUID of PU P#0 in path ./hwloc-x86-cpuid/pu0 ...
        Gathering CPUID of PU P#1 in path ./hwloc-x86-cpuid/pu1 ...
        Gathering CPUID of PU P#2 in path ./hwloc-x86-cpuid/pu2 ...
        Gathering CPUID of PU P#3 in path ./hwloc-x86-cpuid/pu3 ...
        Summary written to ./cpuid/hwloc-cpuid-info
.
.\" **************************
.\"    Return value section
.\" **************************
.SH RETURN VALUE
Upon successful execution, \fBhwloc-gather-cpuid\fR will exit with the code 0.
.
.PP
\fBhwloc-gather-cpuid\fR will return nonzero exit status if any kind of error occurs,
such as (but not limited to) failure to create the output files.
.
.\" **************************
.\"    See also section
.\" **************************
.SH SEE ALSO
.
.ft R
hwloc(7), hwloc-gather-topology(1), lstopo(1)
.sp
